Showing papers by "Oregon Health & Science University published in 1981"

The Pressure Sore: Pathophysiology and Principles of Management

Abstract: The pressure sore is a common clinical problem, although its pathophysiology and management are poorly appreciated by many physicians. The impact of these lesions in terms of patient morbidity and rehabilitation, and health care expenditures is great. Shearing forces, friction and moisture, as well as pressure, contribute to the development of these sores. This paper reviews the clinical settings, causative factors, complications, and principles of prevention and management of the pressure sore. Early surgical consultation is important, because of the deceptive nature and multiple sequelae of these wounds.

Central shunt flows and pressures in the mature fetal lamb

Abstract: Two to eight days after surgery, we determined biventricular cardiac output with the microsphere-dilution method and individual ventricular output with an electromagnetic flow sensor in 12 fetal lambs. Mean biventricular output was 462 ml.min-1.kg-1. Right ventricular output was 60%, pulmonary blood flow was 6%, blood flow in the ductus arteriosus was 54%, flow through the foramen ovale was 34%, and flow in the descending thoracic aorta above the ductus arteriosus was 12% of the biventricular cardiac output. Foramen ovale flow did not correlate with the pressure difference between the atria. The flow though the foramen ovale correlated positively with the flow in the inferior caval vein. It was concluded the shunt flow through the foramen ovale is mainly determined by the kinetic energy of the blood in the "lower atrial inflow tract." Fetal systemic somatic blood flow showed a reliable negative correlation with the oxygen tension in the fetal arterial blood. This was taken as presumptive evidence for long-term autoregulation of flow in the peripheral tissues.

Diurnal Steroid Patterns During Gestation in the Rhesus Macaque: Onset, Daily Variation, and the Effects of Dexamethasone Treatment

Abstract: Serum samples for cortisol, estradiol-1713 (E,), and progesterone analysis were obtained twice daily or more frequently to determine the onset of diurnal steroid patterns in the maternal circulation of pregnant rhesus monkeys. The expected a.m./p.m. fluctuations in serum cortisol (3 1.6/22.9 �zg/dI) were evident from Day 25, whereas nocturnal elevations in progesterone (9.62/16.3 1 ng/ml) were demonstrable on Day 30, and diurnal increments in E2 (283/138 pg/mI), coincident with those of cortisol, appeared about Day 40. Microscopic examination of fetal adrenals from rhesus embryos (ages 30 to 50 days) indicated that the gland differentiates and undergoes extensive development when diurnal E2 release first appears. Administration of 1.0 mg of dexamethasone twice daily to pregnant animals on Days 124 to 130 was accompanied by 1) complete suppression of cortisol release, 2) loss of the diurnal E2 pattern, which was associated with a marked reduction in serum E2, and 3) eventual loss of the nocturnal elevation in serum progesterone without altering its basal levels. Similar treatment earlier in gestation reduced serum levels of both cortisol and F2 without influencing the diurnal serum patterns of these hormones or progesterone. These results support the concept that maternal estrogen levelsdepend on a functional fetaladrenal and further suggest the hypothesis that the inversepatternsin serum cortisoland progesterone are relatedto alteredbinding of progesterone to serum proteins as adrenal activity varies throughout the day. Further evidence supporting the hypothesis of steroid-serum protein interaction was the appearance of nocturnal increments in serum progesterone in ovariectomized animals treated with Silastic capsules containing progesterone and the absence of such increments in similarly treated ovairectomized animals after pituitary stalk section to suppress circadian adrenal activity. It is now clear that diurnal rhythms in serum E3 and progesterone as well as cortisol are present during most of gestation in the rhesus macaque, but the physiological importance of such rhythms remains to be elucidated.

Heterologous desensitization of leukocytes: a possible mechanism of beta adrenergic blockade in atopic dermatitis

Abstract: Studies of mononuclear leukocytes from patients with atopic dermatitis showed depressed cyclic AMP (cAMP) responses after exposure to isoproterenol, histamine, and prostaglandin E1. Because plasma and tissue histamine levels are elevated in atopic dermatitis, we questioned whether histamine or other mediators might be responsible for cAMP abnormalities. We found that exposure of normal cells to low (10(-6)M) concentrations of histamine, isoproterenol, or prostaglandin E desensitized the cells to subsequent stimulatory concentrations of any of the agonists. This heterologous desensitization occurred within 15 min and persisted for days, with gradual recovery of cAMP responses roughly paralleling those of cells from patients with atopic dermatitis. These findings provide a possible explanation for Szentivanyi's beta adrenergic blockade theory and the depressed leukocyte cAMP response to multiple agonists in atopy.

Mechanism for improved cardiac performance with arteriolar dilators in aortic insufficiency.

Abstract: To determine how arteriolar dilation improves cardiac performance in aortic insufficiency, we evaluated the acute effects of hydralazine in 10 patients with chronic severe aortic insufficiency. Control measurements of intracardiac and intravascular pressures, cardiac output and left ventricular volumes were obtained at cardiac catheterization. Hydralazine, 0.3 mg/kg i.v. (maximal dose 20 mg), was administered and all measurements were repeated 30 minutes later. A reduction in systemic vascular resistance from 1264 to 710 dyn-sec-cm-5 was associated with significant increases in forward cardiac index (2.9 to 5.1 l/min/m2) and stroke volume index (37 to 55 ml/m2). Left ventricular end-diastolic pressure was reduced from 19 to 12 mm Hg. There was a significant reduction in mean arterial pressure (88 to 83 mm Hg) and a significant increase in heart rate (81 to 94 beats/min). Regurgitant stroke volume was reduced by more than 10 ml/m2 in seven patients and for the group was significantly reduced, from 65 to 53 ml/m2. Regurgitant fraction was reduced in all patients; the overall reduction from 0.64 to 0.48 was highly significant. Ejection fraction increased more than 0.10 in four patients, by 0.08 in an additional patient and for the group increased significantly from 0.50 to 0.57. Left ventricular end-diastolic volume decreased by more than 25 ml/m2 in four patients, by 19 ml/m2 in an additional patient and was decreased significantly, from 208 to 190 ml/m2, for the group. Arteriolar dilators improve cardiac performance in aortic insufficiency by reducing the amount of aortic regurgitation and, in some patients, by substantially improving systolic pump fraction. These data suggest a role for arteriolar dilators in the management of selected patients with aortic insufficiency.

Osmotic blood-brain barrier disruption: pharmacodynamic studies in dogs and a clinical phase I trial in patients with malignant brain tumors.

Abstract: Patients with solid tumor malignancies who failed extensive front-line treatments were treated with high-dose BCNU followed by autologous bone marrow transplantation. Since 1976, 14 patients were treated in this program with BCNU doses ranging from 600 to 1500 mg/m2 over 2 days. Three patients developed pulmonary toxicity only a few weeks after receiving high-dose BCNU at total doses of 900, 1000, and 1500 mg/m2. Two of the three patients had had prior irradiation to the primary tumor. The third patient did not have prior irradiation to the chest but had received prior nitrosourea therapy. The use of high-dose BCNU in transplantation may be limited to early pulmonary toxicity.

Digoxin Retinal Toxicity: Clinical and Electrophysiologic Evaluation of a Cone Dysfunction Syndrome

Abstract: • A 70-year-old man was studied both during and after resolution of clinical digoxin toxicity using color vision tests, ganzfeld electroretinography, and electrooculography. Concomitant administration of quinidine sulfate probably contributed to digoxin toxicity. Abnormalities in color vision and subnormal amplitude and prolonged implicit time for cone-mediated electroretinogram (ERG) responses suggested a cone dysfunction syndrome. The electro-oculographic light-to-dark ratio during clinical toxicity was high for our laboratory, but this is probably normal. Notable improvement was seen in color vision and the ERG after cessation of digoxin therapy. Inhibition of sodium-potassium adenosine triphosphatase by digoxin probably influences normal uptake of extracellular potassium by Muller's cells and other retinal neurons. This mechanism may contribute to subnormal, prolonged cone-mediated ERG responses in retinal toxic reactions from cardiac glycosides.

Valve prosthesis--patient mismatch. A long-term sequela.

Abstract: A patient underwent mitral valve replacement in 1966 for severe mitral valve disease. The initial clinical result was excellent but symptoms recurred nine years later, and since 1969 he has had progressive cardiac enlargement. At present he is in functional class II and has massive cardiomegaly with gross enlargement of the left atrium, right ventricle, and right atrium. Cardiac catherisation showed "normal" prosthetic valve function, but on moderate exercise he developed severe left atrial and pulmonary arterial hypertension. His clinical course illustrates a long-term sequela of "valve prosthesis--patient mismatch".

Facial Paralysis in the Newborn

Abstract: A group of 95 patients with facial paralysis in the neonatal period are presented. In 74 patients it was believed to be secondary to trauma associated with pregnancy and delivery, and in 21 to be secondary to congenital lesions. The cause, extent, and clinical course of the paralyses are discussed. A classification is outlined to help in organizing a logical and systematic evaluation plan for these patients. Patients may be divided into four groups based on the time they are seen after birth, whether the nerve is stimulable, or whether the nerve loses its stimulability. On the basis of this classification, electromyogram studies, and roentgenographic findings, a presumptive diagnosis may be made and a treatment plan formulated. The treatment plan is based on the diagnosis, facial nerve excitability testing, and degree of deformity present. If there is evidence of facial nerve disruption, a facial nerve exploration is indicated. In congenital cases, reanimation procedures may be necessary.

Pseudogout Mimicking Systemic Disease

Abstract: Pseudogout is a great mimicker of other forms of arthritis, often leading to diagnostic confusion. The association of pseudogout and fever is less widely recognized. We describe eight patients in whom fever was a prominent manifestation of pseudogout leading to misdiagnosis, overinvestigation, and a delay in appropriate treatment. ( JAMA 1981;246:1438-1440)

Maculopathy in Cynomolgus Monkeys: A Correlated Fluorescein Angiographic and Ultrastructural Study

Abstract: • Maculae of seven cynomolgus macaque monkeys ( Macaca fascicularis ) showing abnormalities in color fundus photographs and fluorescein angiograms were studied in serial sections by light and electron microscopy and compared with three eyes without clinically visible defects in the macula. Maculae that showed hyperfluorescent nonleaking window defects showed no drusen or interruptions in the retinal pigment epithelium (RPE). Six of these monkeys had misshapen foveal depressions, all showed some degree of photoreceptor degeneration, and one had cells in Bruch's membrane. Bright yellow spots correlated with scattered RPE filled with lipid vacuoles. Shallow RPE elevations correlated with diffuse nonleaking window defects. Patches of RPE deficient in melanin occurred at sites of hyperfluorescence. Quantitative studies showed that maculae with window defects had more lipofuscin and less melanin per RPE cell. Maculae deemed normal by photography showed degenerating photoreceptors.

Mixed invasive infection with Alternaria species and Curvularia species.

Abstract: Alternaria and Curvularia species were isolated from the nasal septum of a neutropenic patient and tissue invasion was documented histologically. The patient recovered without the use of systemic antifungal agents following surgical excision of the nasal septum and spontaneous resolution of neutropenia.

Training psychiatrists to work with community support systems for chronically mentally ill persons.

Abstract: Community support programs are becoming a major priority in community mental health centers throughout the country. The authors present a training design that integrates principles and skills associated with this model into a 4-year residency training program. The aim of such programs is to keep young psychiatrists involved and in the forefront of the newer approaches to the treatment of chronically mentally ill persons.

Improvement in the relationship between flow to ischemic myocardium and the extent of necrosis with glycolytic intermediates that decrease blood oxygen affinity in dogs.

Abstract: Reducing blood oxygen affinity may enhance myocardial oxygen delivery during ischemia. We evaluated this hypothesis in awake, previously instrumented dogs that received a 20 ml/kg infusion of a solution of dihydroxyacetone, phosphate, and pyruvate after acute occlusion of either the left anterior descending or circumflex coronary artery. This infusion reduced blood oxygen affinity (BOA) after 2 hours; the P50 increased from 29.9 +/- 0.7 torr (mean +/- SD) to 32.1 +/- 0.6 torr; P less than 0.01 (BOA group). Four dogs received 20 ml/kg of phosphate and pyruvate solution to assess volume effects (V group), and five dogs were controls (C group). The 2-hour P50 values in V and C were unchanged. Regional flow (15-mum spheres) reduction 2 hours postocclusion was compared to the percent tissue infarcted determined by histology 7-9 days after occlusion for multiple samples from the endocardial layer of the left ventricle. When flow was less than 40% of normal, V and C had 55% infarction while BOA had 37% (P less than 0.05); at flow less than 20% of normal, V and C had 79% infarction while BOA had 38% (P less than 0.001); and at less than 10% of normal, V and C 87% and 94% infarction, respectively, while BOA had 56% (P less than 0.001). Reducing blood oxygen affinity after coronary artery occlusion significantly decreased the extent of myocardial necrosis for the same degree of ischemia. Reducing BOA may increase oxygen delivery to ischemic myocardium when flow is restricted.

Effect of formalin toxoiding on Pseudomonas aeruginosa toxin A: biological, chemical, and immunochemical studies.

Abstract: We investigated the effect of Formalin toxoiding on the biological, chemical, and immunological activities of Pseudomonas aeruginosa toxin A. Formalin treatment alone resulted in a 1,000-fold decrease in toxin-induced cell cytotoxicity and altered the antigenicity of the toxin A molecule without adversely affecting enzymatic activity. Competitive blocking experiments indicated that Formalin-mediated detoxification proceeded via alterations in a region of the toxin molecule other than the active site of the enzyme. The addition of lysine to Formalin-toxin mixtures not only increased the rate and extent of detoxification and antigenic alteration, but also completely destroyed enzymatic activity. The immunogenicities of different toxoids varied substantially. Upon dialysis and storage, Formalin-derived toxoids underwent partial toxic reversion, whereas a Formalin-lysine-derived toxoid did not. The sodium dodecyl sulfate-polyacrylamide gel patterns of Formalin- and Formalin-lysine-treated toxins indicated that these treatments caused the formation of a heterogenous group of high-molecular-weight species and produced substantial changes in the electrophoretic mobility of toxin A. Images

Carcinoma of the Cervix Involving the Duodenum: Case Report and Review of the Literature

Abstract: We report a patient with squamous cell carcinoma of the cervix metastatic to the duodenum in whom the diagnosis was made at endoscopic biopsy of an obstructing pyloric mass. Failure to consider metastatic disease as the cause of an abnormal appearance of the duodenum resulted in a considerable delay in diagnosis. We present a brief review of cervical carcinoma metastatic to the bowel.

Cardiac valve replacement in patients over 75 years of age.

Abstract: Elderly patients with symptomatic cardiac valvular malfunction have a grave prognosis if managed medically but can be offered a reasonable chance for long-term survival and a good chance for improvement by replacement of the malfunctioning valve. A series of patients 75 years of age and older who underwent aortic valve replacement (31 patients) mitral valve replacement (9 patients), or combined valve replacement (on patient) has been reviewed. The overall operative mortality for aortic valve replacement was 23% (17% over the past 5 years) and the 5-year actuarial survival was 54 +/- 11%. The operative mortality for mitral replacement was 11% and the 5-year actuarial survival was 55 +/- 21%. The average hospital stay for survivors was 19 days after aortic valve replacement. Four patients have had embolic events since valve replacement, 3 after aortic and one after mitral valve replacement. The addition of coronary artery bypass surgery to the valve replacement procedure is becoming more frequent and may have contributed to improved operative survival. A literature review of reported clinical experience shows that the advancement of cardiac surgery has permitted a redefining of the group thought as "elderly", and that this group has an improved operative survival with the improvements in cardiac valve surgery.

Structural organization of the heterochromatic region of human chromosome 9

Abstract: Giemsa-11, G-banding and Lateral Asymmetry staining techniques were used to define the substructure of the C-band heterochromatin of human chromosome 9, in a sample of 108 different chromosomes 9, from 54 individuals. In this sample, the juxtacentromeric portion of the C-band region stained positive by the G-banding technique while Giemsa-11 delineated a more distally located block. Examination of the pericentric inversions generally revealed that the entire C-band region is changed with the substructural organization left intact; i.e. the G-band is proximal, the G-11 distal to the centromere. The “partial pericentric inversions” were found to have larger than average amounts of G-band heterochromatin on the short arm. The G-11 staining was in its usual position on the long arm with none on the short arm. Such apparent inversions therefore may not represent true inversions. — Long heterochromatic regions frequently had a segmented appearance when stained with G-11; there was a dark G-band within the pale heterochromatic region when stained with the G-banding technique which corresponded in location to the achromatic gap produced by G-11. This extra G-band may have been derived from the juxtacentromeric G-band by processes analogous to unequal crossing over. — Simple lateral asymmetry was consistently present only in the G-band heterochromatin of those chromosomes 9 containing large blocks of G-band positive material. Examination of the portion of the C-band which would correspond to the G-11 positive material revealed no consistent patterns of asymmetry. Usually both strands were heavily stained and symmetrical but occasionally there were light areas present on one strand suggestive of compound lateral asymmetry.

Human kidney preservation by intracellular electrolyte flush followed by cold storage for over 24 hours.

Abstract: Many transplant teams are reluctant to accept kidneys preserved with intracellular electrolyte flushing followed by simple cold storage when preservation time exceeds 24 hr. This study from one center is a comparison of 63 primary cadaver kidney grafts preserved with Collins 2 solution flush followed by cold storage for 9 to 23 1/2 hr to 42 primary cadaver kidney grafts preserved by the same method for 24 to 44 1/2 hr. Kidneys cold-stored for over 24 hr had a significantly increased requirement for dialysis in the first week following transplantation (55% versus 30%). One-month serum creatinine nadirs and actuarial graft survivals were not significantly different. Cadaver donor methylprednisolone (30 to 60 mg/kg) 2 to 9 hr prior to kidney removal reduced the requirement for first-week hemodialysis in the kidneys cold-stored for over 24 hr (23% versus 69%, P under 0.05). A human kidney preserved by the same method and cold-stored for 61 hr was successfully transplanted into a 38-year-old myelodysplastic. Satisfactory human kidney preservation can occur with intracellular electrolyte flush solutions followed by cold storage for over 24 hr when the warm ischemia time is very short.

Ventriculocisternal cerebrospinal perfusion in unanesthetized fetal lambs

Abstract: Methods have been developed for the placement of cannulas in the lateral cerebral ventricle and cisternum magnum of the fetal lamb. Three to seven days after surgery, perfusion of the cerebral ventricular system was carried out in unanesthetized lambs in utero. Artificial cerebrospinal fluid (CSF) was perfused at 123 microliter/min for 4-5 h with no change in fetal arterial O2 pressure, CO2 pressure, pH, mean arterial blood pressure, or heart rate. The preparation is suitable for measurements of net formation of fetal central CSF and also for producing changes in the ionic composition of the fetal CSF.

Dopamine: effects on prolactin and luteinizing hormone secretion in ovariectomized rhesus macaques after transection of the pituitary stalk.

Abstract: Luteinizing hormone (LH) and prolactin (PRL) levels were compared in the serum of ovariectomized rhesus macaques (Macaca mulatta) with pituitary-intact (PI) and surgically transected pituitary stalks (SS). After stalk sectioning, LH levels declined and PRL levels rose dramatically. Chronic infusion of intermittent pulses of gonadotropin-releasing hormone (GnRH; 1 microgram/min for 6 of every 60 min) into SS females reinitiated LH secretion within a few days despite increased PRL secretion. Continuous infusion of dopamine (10 micrograms/min/kg of body weight) for 9 days suppressed PRL levels in GnRH-infused SS females to near normal without alteration in basal serum LH levels or pulsatile LH release. A comparable dopamine regimen also failed to modify serum LH patterns in PI monkeys. Immediately after cessation of dopamine, serum PRL levels rose sharply in both PI and SS animals. Injection of estradiol benzoate (42 micrograms/kg of body weight) into SS monkeys receiving GnRH infusions resulted initially in LH suppression and then in LH release. However, the magnitude of LH release was less and the latency to its onset was longer in SS animals given estrogen than in PI controls with similar serum estrogen concentrations. It is unclear whether the atypical pattern of the estrogen-induced LH release in SS monkeys was due to hyperprolactinemia or other deficiencies in this GnRH-infused model. However, these data indicate that the response of gonadotropes to GnRH stimulation was not altered by a direct action of either PRL or dopamine on the pituitary gland. Conversely, dopamine directly suppressed the lactotrope, which became hypersecretory immediately upon dopamine withdrawal. We have concluded that estrogen-induced inhibition and subsequent augmentation of LH release represents a direct action at a pituitary locus, although effects at additional, nonpituitary loci are not precluded.

Haemophilus parainfluenzae Thoracic Empyema

Abstract: • To our knowledge, thoracic empyema caused by Heamophilus parainfluenzae has not been described previously. A case occurred in the setting of alcoholism and chronic obstructive pulmonary disease. We note the similarity to pulmonary infections with H influenzae and discuss the implications for antibiotic therapy. ( Arch Intern Med 1981;141:940-941)

Local variations in arrests of psychiatric patients.

Abstract: The involvement of psychiatric patients in the criminal justice system has come under increasing attention in the psychiatric literature within the past five years. Research conducted by Zitrin et aI, I Durbin et aF and Sosowsky:l demonstrated that mental patients are arrested more frequently than nonmentally ill persons in three distinctly different regions of the United States. That mentally ill persons, or at least certain groups of mentally ill individuals, are arrested more frequently than the average person seems now to be accepted. More recent research, conducted by Steadman et al,4 is aimed at explaining these apparently high arrest rates. Steadman found three factors which contributed to increased arrest rates: history of prior arrest, age and hospital admission diagnosis. Those patients with arrest records were younger than patients with no arrest experience. The patients with admitting diagnoses of substance abuse or personality disorders were arrested significantly more often than those patients with other admitting disorders including psychosis. In relation to arrest history, Steadman found that patients with prior arrests were more likely than other patients to be arrested again. In a second study, Steadman\" compared arrest rates of mental patients with those of criminal offenders. He found that mental patients with no arrest history prior to psychiatric hospitalization had a subsequent arrest pattern no different from the general population; however, with multiple arrests before psychiatric hospitalization the subsequent arrest rates of these patients is indistinguishable from criminal recidivists. Steadman demonstrates that there are sub-groups of mentally ill persons who are arrested on mUltiple occasions and that these patients, when lumped with other hospitalized patients, distort arrest rates for the larger group. He concludes: \"The issue is not so much that there are more mentally ill people at risk for criminal activity in the community; more accurately, the problem seems to be that there are more criminals in mental hospitals in the first place. \"6